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排序方式: 共有214条查询结果,搜索用时 62 毫秒
181.
猪流行性腹泻(porcine epidemic diarrhea,PED)是一种可引起仔猪高致死率的传染性疾病,尽管已有灭活疫苗和减毒活疫苗上市,但由于病毒变异频繁导致保护效力欠佳,发病率依然居高不下。本研究首次制备了PED mRNA候选疫苗,并在小鼠和妊娠母猪上评价了其免疫原性,证明了基于病毒受体结合区异源二聚体的mRNA候选疫苗具有良好的免疫原性,可在小鼠上高效诱导体液和细胞免疫应答,单次免疫血清中和抗体滴度达到1:300以上,并在妊娠母猪上诱导了与灭活疫苗相近的中和抗体水平,实现了100%抗体转阳。本研究为PED mRNA疫苗的进一步产业化奠定了基础。 相似文献
182.
Tao Zhang Junhong Jin Shenglin Yang Guang Li Jianming Jiang 《Carbohydrate polymers》2009,78(2):364-366
A series of dihydroxy poly(p-phenylene benzobisoxazole) (DHPBO) were prepared by introducing binary hydroxyl groups, that is 2,5-dihydroxyterephthalic acid (DHTA) into poly(p-phenylene benzoxazole) (PBO) macromolecular chains and then DHPBO fibers were prepared by dry-jet wet-spinning method. As indicated by Fourier transform infrared spectrum (FTIR), hydroxyl groups were incorporated into DHPBO polymer chains successfully and intermolecular hydrogen-bonds had been formed. The effects of hydroxyl groups on the compressive property of PBO fibers were investigated by elastic loop test method. The test results showed that the compressive strength of DHPBO fibers with 10 mol% DHTA content were obviously higher than that of PBO fibers. 相似文献
183.
Color image detection by biomolecular photoreceptor using bacteriorhodopsin-based complex LB films 总被引:1,自引:0,他引:1
Hyun-Goo Choi Woo-Chul Jung Junhong Min Won Hong Lee Jeong-Woo Choi 《Biosensors & bioelectronics》2001,16(9-12):925-935
A biomolecular photoreceptor consisting of bacteriorhodopsin (bR)-based complex Langmuir–Blodgett (LB) films was developed for color image detection. By mimicking the functions of the pigments in retina of human visual system, biomolecules with photoelectric conversion function were chosen and used as constituents for an artificial photoreceptor. bR and flavin were deposited onto the patterned (9-pixelized) ITO glass by LB technique. A 9-pixel biomolecular photoreceptor was fabricated with a sandwich-type structure of ITO/LB films/electrolyte gel/Pt. Since each functional molecule shows its own response characteristic according to the light illumination in the visible region, the simplified knowledge-based algorithm for interpretation of the incident light wavelength (color) was proposed based on the basic rule describing the relationship between the photoelectric response characteristics and the incident light wavelength. When simple color images were projected onto the photoreceptor, the primary colors in visible light region, red, green, and blue were clearly recognized, and the projected color images were fairly well reproduced onto the color monitor by the proposed photoreceptor with the knowledge-based algorithm. It is concluded that the proposed device has a capability of recognizing the color images and can be used as a model system to simulate the information processing function of the human visual system. 相似文献
184.
Junhong Min Hyun-Goo Choi Byung-Keun Oh Won Hong Lee Se-Hwan Paek Jeong-Woo Choi 《Biosensors & bioelectronics》2001,16(9-12):917-923
Image extraction and visual information processing using bacteriorhodopsin (bR)-based bioelectronic devices is presented. Image extraction was achieved using a photoreceptor consisting of bR and spiropyran films. The undesired signals from the photoreceptor were automatically eliminated from the whole signal by spiropyran films acting as an optical noise filter that increases the target signal to an undesired signal ratio. For the information processing, the photoreceptor consisting of bR and lipid films deposited with different configurations was used and the target signals were processed to achieve the pattern recognition. The pattern recognition was based on not only the response variability of bacteriorhodopsin, induced by different film configurations, but also on the initial learning process. The input patterns were predicted by simple calculation with the known signals through the initial learning process. 相似文献
185.
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187.
The production of linolenic acid in mycelial lipids reached 0.31 mg/ml of culture broth when Mortierella isabellina was cultivated in a medium consisting of 2% octadecanol, 1% yeast extract, and 25 mmol/L of Mg2+ at 23°C for 5 days. Cultivation conditions were studied, and the results showed that (i) a suitable concentration of Mg2+ in the medium caused an increase in mycelial mass as well as linolenic acid production; (ii) when incubated at 23°C, maximal
linolenic acid productivity was reached, although a higher content of the acid in total fatty acids was found at the lower
temperature; (iii) the effect of substrate concentration on linolenic acid yield showed that the latter increased with concentration
of substrate, and maximal linolenic acid yield was obtained with concentrations of 2% octadecanol and 1% yeast extract.
Received: 27 November 2000 / Accepted: 22 June 2001 相似文献
188.
Constitutively active PDX1 induced efficient insulin production in adult murine liver 总被引:6,自引:0,他引:6
Imai J Katagiri H Yamada T Ishigaki Y Ogihara T Uno K Hasegawa Y Gao J Ishihara H Sasano H Mizuguchi H Asano T Oka Y 《Biochemical and biophysical research communications》2005,326(2):402-409
To generate insulin-producing cells in the liver, recombinant adenovirus containing a constitutively active mutant of PDX1 (PDX1-VP16), designed to activate target genes without the need for protein partners, was prepared and administered intravenously to streptozotocin (STZ)-treated diabetic mice. The effects were compared with those of administering wild-type PDX1 (wt-PDX1) adenovirus. Administration of these adenoviruses at 2x10(8)pfu induced similar levels of PDX1 protein expression in the liver. While wt-PDX1 expression exerted small effects on blood glucose levels, treatment with PDX1-VP16 adenovirus efficiently induced insulin production in hepatocytes, resulting in reversal of STZ-induced hyperglycemia. The effects were sustained through day 40 when exogenous PDX1-VP16 protein expression was undetectable in the liver. Endogenous PDX1 protein came to be expressed in the liver, which is likely to be the mechanism underlying the sustained effects. On the other hand, albumin and transferrin expressions were observed in insulin-producing cells in the liver, suggesting preservation of hepatocytic functions. Thus, transient expression of an active mutant of PDX1 in the liver induced sustained PDX1 and insulin expressions without loss of hepatocytic function. 相似文献
189.
Pingnan Sun Junhong Zheng Guizhou She Xiujing Wei Xiaoyu Zhang Haijun Shi Xiaoling Zhou 《Cell and tissue research》2013,352(3):761-768
During acute or chronic hepatitis B virus (HBV) infection, the virus can invade the male reproductive system, pass through the blood–testis barrier and integrate into the germ line, resulting in abnormal spermatozoa. However, the pathway remains unclear. The asialoglycoprotein receptor (ASGR), a potential receptor for HBV, is mainly distributed in hepatocytes. We have examined the distribution of ASGR in human testis and found it in the seminiferous tubules and interstitial region but its enrichment in human testis is much lower than that in liver. By multiple immunoenzyme histochemistry staining, ASGR was precisely co-localized with vimentin (Sertoli cell marker) but not proliferating cell nuclear antigen (spermatogonial cell marker) in testis tissue. ASGR was expressed in human Leydig cells, stromal cells in the seminiferous tubules and Sertoli cells but seldom in spermatogonial cells. Therefore, ASGR could provide HBV with access to the luminal compartment of human testis. The mechanism by which HBV invades germ cells remains unknown. 相似文献
190.